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As I mentioned before, sometimes I do Lunars with
my pocket sextant, just for fun.
Here is an example. Let me begin with my usual
observation using SNO-T:

January 25, GMT 20:15 T=35 (F), pressure 39.4
Sun-Moon, at 88degrees
sextant SNO-T  IC=-0.5, 13 observarionr Average error=-0.3 sigma=0.2

Same, GMT 21:00, 6 observations Average error=-0.2 sigma=0.1

Now the same with Pocket Troughton and Simms,
of 2 inches radius. I give row observations, no averaging
(remember, the scale reads to 1' and even this with difficulty:-)
Assumed IC=0.
GMT 21:09:40 sextant reading 88d40' error 0.1
GMT 21:11:50 sextant reading 88d41' error 0.2
GMT 21:14:15 sextant reading 88d42' error 0.3
GMT 21:17:25 sextant reading 88d43' error 0.1
GMT 21:19:10 sextant reading 88d43' error=-0.5

Average error: 0.04, sigma=0.3
Accident? Well, I can only repeat the words of Humboldt:
such accidents are frequent:-)

You see, the results with a pocket 2 inch sextant seem better
than with SNO-T. And this is not the first time.
Of course, using this pocket sextant is MUCH harder than a
normal one, first of all because of its tiny telescope with tiny
object glass and very small field of view.
(I find impossible to use it with the stars, for example).
Another problem is that I cannot check IC with Sun (there is no horizon
filter).
So I just do it with remote wires, horizon, whatever is available.
Neither I can do perpendicularity check, just don't know how:-)

Alex.
P.S. If you wish to check the reduction, my position is 40d27.2 N,
86d55.8 W.
And I use Frank's online calculator.


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